By Edward Qorro
One of nature's greatest spectacles unravels each year in the Serengeti, the crown jewel of the African savannah that stretches 30,000 sq km from Kenya's Masai Mara National Reserve to Tanzania's Serengeti National Park.
It's a sight to behold as the even-toed horned animals brave the raging waters of the Mara in Tanzania en route to the Masai Mara plains on the Kenyan side as part of what has come to be known as the great wildebeest migration.
The 1.5 million-odd wildebeests, or gnus, aren't alone in this odyssey. Around 200,000 zebras, 300,000 Thomson's gazelles and 120,000 elands also make the arduous and often perilous, round-the-year journey spanning nearly 1,000km.
The migration commences in the Ndutu plains, which stretch from the western side of the Ngorongoro Conservation Area to the southeastern section of Serengeti National Park.
This expansive area features part of Ngorongoro, including the Olduvai Gorge, the site where fossilised remains of the first known humans were found.
"The wildebeest migration is a phenomenon that headlines Tanzania's status as a tourism paradise," Catherine Mbena, senior conservation officer in charge of communications at the Tanzania National Parks Authority, tells TRT Afrika.
Instinct for survival
In the prelude to mass migration, calving wildebeest are seen putting the young through their paces within minutes of birth. This usually occurs from mid-January to February unless safety instincts kick in and wildebeest herds postpone their synchronised reproduction cycle.
Based on observation records, wildebeests prefer the Ndutu area for calving for reasons ranging from safety to abundant pastures for grazing.
"This area is famed for its short-grass plains that offer pastures rich in nutrients such as phosphorous, calcium and magnesium, all of which the young ones get through their mothers' milk," Catherine points out.
Better nutrition enables the young wildebeest to gain coordination faster than other ungulates, including getting on their feet two to three minutes after birth and being able to sprint with the herd after just five minutes.
Juveniles continue to mature on the short-grass plains well into March and April, gaining strength for the long migration to the North following the rains and the growth of new pastures.
The herd next heads to the Seronera area, which is at the centre of Serengeti National Park.
Along the way, they brave predators such as lions, cheetahs and hyenas — an experience that hardens them in preparation for crossing the mighty Mara.
"During this time, a large portion of Serengeti National Park experiences long, dry spells. This forces the wildebeests to move to Kenya, where there are more rains," Catherine tells TRT Afrika.
Selective migration
Contrary to perception, not all wildebeest shift base to Kenya. Various studies have shown that only between 25 and 30 per cent of the total wildebeest on the migration route remain in Kenya.
This is because the Masai Mara National Reserve is too small to accommodate the entire migratory wildlife population.
Even after crossing the river, wildebeest can be spotted roaming the Tanzanian side of the savannah.
"The wildebeest hardly spend four months on the Kenyan side. They will be back to base by September," explains an official of the Tanzania National Parks Authority.
Climate impact
According to conservationists, prolonged, delayed or even heavy rains may alter the normal seasonal movement of large herds of wildebeest and zebra.
They may stay in one region longer and disperse over a wider area instead of moving on their usual mass migration toward wetter regions.
In 2022, for instance, dry spells on the Kenyan side prompted wildebeest herds to delay their migration pattern.
Although crucial for the Tanzanian economy, tourism is also a potential disruptor.
Every year, vehicles ferrying tourists dot the banks of the Mara to catch a glimpse of the migrating wildlife. Sometimes, the sheer number of tourists pitching camp in the area becomes a nuisance for the wildebeest herds fighting for survival against many odds.
"The noise of engines revving and excitable tourists can affect the wildebeest. They don't want to be disturbed when crossing the river," says Catherine.
The Tanzania National Parks Authority has been engaging with tour operators on how to address the situation.
In trying to escape the noise, wildebeest could attempt to cross the river from different points, inviting more danger. Unable to scramble up steep banks, thousands anyway drown in a mass panic or get mauled by crocodiles.
This heart-stopping natural migration spectacle remains Serengeti National Park's calling card. It has been voted Africa's best wildlife reserve for five consecutive years and is categorised as one of the world's top natural wonders.
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